Ecosystems

Organisms interacting with one another in their physical

surroundings

What make an ecosystem?

• Biotic: living things• Examples: bugs, plants, humans, things that

have died• Abiotic: nonliving things – never been alive• Water, air, rain, sun, weather, rocks

Community Dwellers

• Community: organisms that dwell together• Contains many different types of animals and

plants• Population: all the same type of organism• Just dogs or just cats or just birds• Species: specific type of population; have

similar characteristics• Example: dogs – great dane, cocker spaniel,

german shepherd

Community

Community

Population

Populations

Species

• Adaptation: structure or behavior that enables a species to survive and reproduce

• Niche: special role an animal has in its enviornment

• Worm: decomposer, breaks down rotting things, adds nutrients (nitrogen) to the earth

How big can an ecosystem be?

• Can be as small as a puddle• Or as big as an ocean• Many ecosystems are made up of many

ecosystems!!

Changing Ecosystems

• How can ecosystems change?• Human impact• Deforestation – cutting down forests for cities• Pollution – • Natural Disasters• Earthquakes • Volcanic Eruptions• Violent Storms• Drought

Deforestation

Pollution

Pollution

Pollution

Adaptation• Clear fur to camouflage • Black skin to absorb heat• Hollow fur to trap heat and

help bear to float• Thick patting on feet to insulate

from cold• Wide paws act as snowshoes on

the snow and ice• Claws are used to catch prey

and to climb on the ice• Hair grows between the pads of

the feet to help prevent the bear from slipping on the ice

The importance of the Sun

• Plants convert the Sun’s energy through photosynthesis

• ALMOST all life of earth depends on the Sun for energy either directly or indirectly

• Plants take in water and CO2 and changes them into sugar and oxygen.

• Sugar is the plant’s food and contains the plant’s stored energy.

• **When animals eat the plants they also use the solar energy stored in the sugar.**

Photosynthesis

• Organisms that carry out photosynthesis contain chlorophyll (makes plants green)

• Stores light energy from the Sun• Non-green need the Sun too! – We obtain energy from plants – We obtain energy from animals that get energy from

plants!– Fungi gets energy from breaking down remains for dead

animals and plants.

• Draw picture from page 15

PHOTOSYNTHESIS